Follow-up to the salvaged early-exit retry fix (#35617): the debug-browser
launch path was fire-and-forget (stderr to DEVNULL, no logging), so every
platform failure — Windows singleton forward to an existing instance, bad
profile dir, missing shared libraries, policy blocks — collapsed into the
same unactionable 'port 9222 isn't responding yet' message and debug
reports contained nothing.
- launch_chrome_debug() returns a structured ChromeDebugLaunch with
per-candidate attempts (state, exit code, stderr tail)
- browser stderr is captured to <hermes_home>/chrome-debug/launch-stderr.log
- clean exit (code 0) without the port opening is detected as Chromium's
single-instance forward and produces a targeted user hint to close all
running instances of that browser
- crash exits surface the stderr tail (e.g. missing libnspr4.so)
- every spawn/exit is logged to agent.log so hermes debug share captures it
- CLI (/browser connect) and TUI/desktop (browser.manage) both print the hint
Add browser CDP launch candidates for Chrome, Chromium, Brave, and Edge while preserving Chrome-first selection. Retry candidate launch failures instead of giving up after the first executable.
Update /browser CLI and TUI messaging, docs, and tool descriptions from Chrome-only wording to Chromium-family browser support. Add regression coverage for Brave/Edge paths, Chrome-first precedence, fallback launches, and CDP endpoint probing.
Fixes from Copilot's two passes on PR #17238:
* Validate parsed URL once: reject missing host, invalid port, and
unsupported scheme up front so malformed inputs (e.g. http://:9222
or http://localhost:abc) don't fall through to a generic 5031.
* Tighten _is_default_local_cdp to require a discovery-style path so
ws://127.0.0.1:9222/devtools/browser/<id> is not collapsed to bare
http://127.0.0.1:9222 (which would lose the path and break the
connect).
* Move browser.manage into _LONG_HANDLERS so the up-to-10s
launch-and-retry loop runs on the RPC pool instead of blocking the
main dispatcher.
* try_launch_chrome_debug uses Windows-appropriate detach kwargs
(creationflags=DETACHED_PROCESS|CREATE_NEW_PROCESS_GROUP) instead
of POSIX-only start_new_session=True.
* manual_chrome_debug_command uses subprocess.list2cmdline on
Windows so the printed instruction is cmd.exe-compatible.
* Mirror host/port validation in cli.py /browser connect so the
classic CLI never persists an invalid BROWSER_CDP_URL.
Split browser.manage into a small dispatcher with named connect/disconnect
helpers, fold _http_ok / _probe_urls / _normalize_cdp_url out of the nested
probe loop, collapse the failure-message scaffolding, and DRY the chrome
candidate path tables. Behaviour and event shape unchanged.
Detect an actual Chrome/Chromium executable before printing a manual CDP launch command, including common WSL-mounted Windows browser paths, so /browser connect does not suggest google-chrome when it is unavailable.
Share Chrome CDP launch helpers between the classic CLI and TUI so default /browser connect uses loopback consistently, retries local Chrome launch, and reports a copyable manual-start command instead of claiming a dead connection.
